James dewar



(No Model.)

J. DEWAR & B. REDWOOD. I PROCESS OF DISTILLING MINERAL 0111s AND'LIKEPRODUCTS.

No. 419,931. Patented Jan.21,1890,

UNITED STATES PATENT OFFICE.

JAMES DEIVAR, OF CAMBRIDGE, COUNTY OF CAMBRIDGE, AND BOVERTON REDWOOD,OF FINCIILEY, COUNTY OF MIDDLESEX, ENGLAND.

PROCESS OF DISTILL ING MINERAL OILS AND LIKE PRODUCTS.

SPECIFICATION forming part of Letters P Application filed September 3,1889. Serial No. 322,856-

Irance August 30, 1389, No. 200,405; in Belgium August 30 and in ItalyOctober 1, 1889, LI, 233- To all whom it may concern.-

Be it known that we, JAMES DEWAR, professor of chemistry, and BOVERTONRED- WOOD, analytical chemist, citizens of England, residing,respectively, at No. 1 Scroop Terrace, Cambridge, in the county ofCambridge, and at Ballards Lane, Finehley, in the county of Middlesex,England, have invented new and useful Improvements in the Distillationof Mineral Oils and Like Products, (for which we have obtained LettersPatent in France, dated August 30, 1889, No. 200,495; Belgium, datedAugust 30, 1889, No. 87,570; Switzerland, dated August 30,1889, [5 No.1,339; Italy, dated October 1, 1889, Vol.

LI, No. 233, and Great'Britain by an application for patent, whichpatent when granted will bear date June 24, 1889, N 0. 10,277,) of whichthe following is a specification.

In distilling mineral oils-such as natural petroleum or similar oil madefrom shale, coal, or otherbituminous substances-in order to separate thelighter oils, suitable for lamps and other purposes, from the heavieroils, there is frequently a very large residue of heavy oil. Attemptshave been made to obtain lighter oils from such residues or from heavynatural petroleums by causing the vapor generated in the still-boiler topass a heavily-loaded valve, so that the vaporization takes place underconsiderable pressure. It has also been proposed to arrange thestillboiler with its upper part cooled, so that the best volatileportions of the vapor may become more or less condensed and fall backinto the hot liquid below, this mode of operating being commonly termedcracking. Both these methods are objectionable, the former on account ofthe irregularity of the to distillation and the latter on account of thewaste of heat in conducting the cracking process and the slowness andinsufiiciency of the results.

Our invention relates to a method of conducting the distillation bysuitable apparatus in such a manner that we get the benefit of regularvaporization and condensation under high pressure, and that we. may atthe (No sp atent No. 419,931, dated January 21, 1890.

ecimens.) Patented in England June 24, 1889, No. 10,277; .in 1889, No.87,570; in Switzerland August 30, 1889,110, 1,3 39,

same time get such advantage as can be obtained from cracking. For thispurpose we arrange a suitable boiler or retort and a condenser in freecommunication with one another without interposing any valve betweenthem; but We provide a regulated outlet for condensed liquid from thecondenser. We charge and keep charged the space in the boiler or retortand condenser that is not occupied by liquid with gas under considerablepressure, it may be with air or it may be with carbonic-acid gas orother gas that cannot act chemically on the matter treated; Thedistillation and condensation being thus conducted under considerablepressure, which can be regulated at will, We obtain from the heavyresidue a quantity of more or less light oil suitable for illuminatingand other pun poses, which cannot be obtained by distillation underatmospheric pressure. \Ve may also arrange the still-head or upper partof the boiler or retort so as to operate accord- 7o ing to the crackingmethod above referred to, the cracking in this case taking place underhigh pressure instead of being carried on under atmospheric pressure.

The apparatus for effecting disti the manner described may be ar variousways. The accom show one form of apparatus for this purpose, which isthe subject-matter of apatentapplication of even date herewith, SerialNo. 80 322,857..

Figure 1 is a longitudin transverse section. Fig.

llation in ranged in panying drawings a1 and Fig. 2 is a 3 is asectional plan on the line X X of Fig. 1.

A is a fire-place, with fire-door A and ashpit door A, suited forregulating admission of air as required.

Instead of a fire-place with grate for burning solid fuel, any knownburners for liquid or gaseous fuel may be employed. 9

Above the combustion-chamber B is placed.

a metal retort C, which is inclosed within a refractory casing O toprotect the metal from excessive local heating. The incased retort is stuated in a hoating-chamber B, into 5 which the hot products ofcombustion ascend by side ports 13 and from which they pass by centralports B into a flue B communicating with a chimney B The front part ofthe retort C communicates freely with a stillhead 0 provided with apressure-gage C and safety-valve C. The exposed end of the retort C isclosed by a readily-removable cover C provided with a glass gage to showthe level of the liquid in the retort.

D is a pipe-coil situated in a tank D', in which circulation of water ismaintained. The upper end of the coil D communicates by a pipe with thestill-head O and its lower end opens into a hollow column D which isprovided with a glass. gage D and has at the bottom an outlet-pipe D",furnished with a stop-cock or valve.

E is a pump for forcing the oil to be'treated by a pipe E into theretort 0, this pipe preferably extending nearly to the farther end ofthe retort. By another pipe E furnished with a. cock or valve, thecontents of the retort can be drawn off, or this pipe may communicatewith a second retort, which in like manner may be connected with athird, so as to form a series of any required number.

F is an air-compressing pump, by which air or suitable gas is forced bya pipe F into the still-head C or it might be into any other part of theapparatus which is in communication with the still-head. The retort Cbeing partly charged'wi'th oil by the pump E, and the spaces in theretort C in the stillhead 0 and in the condensing-coil D and column D'being charged with air or gas to the desired pressure, the retort isheated, vaporizing the oil under pressure. The oilvapor is condensed inpassing through the coil D and the liquid distillate collects in thecolumn D and is drawn 01f either continu-- ously or intermittently intosuitable receptacles, in which such gas as may be dissolved in theliquid is liberated and can be collected.

By a pipe and cock or a suitably-loaded safety-valve D gas may bewithdrawn from 5 the space above the liquid in the column D Although wehave shown one retort and condenser, there may be several sets of thesein communication with the oil and gas pumps or with each other, suitablecocks or valves being provided in the communicating pipes, so that theseveral retorts may be worked simultaneously or in rotation. From timeto time the cover C of the retort maybe removed to clear out residue.During the distillation such of the vapor as may be condensed in thestill-head C or such liquid as may p ime up into the still-head, flowsback into the body of liquid in the retort. By regulating the heat andpressure to which the retort is subjected the character of thedistillate may be varied, and thus oils more or less light can beobtained to suit various uses. Also, the proportions of the parts may bevaried, and, if necessary, means of cooling may be'applied to thestill-head C Having thus described the nature of our invention and themanner of carrying the same into effect, we claim- The herein-describedmethod of distilling mineral oils and like products, which consists inboth vaporizing them and condensing the generated vapor under aregulated pressure of air or gas, substantially as specified.

In testimony whereof we have signed our names to this specification, inthe presence of two subscribing witnesses, this 13th day of August, A.D. 1889.

JAMES DEWAR. BOVERTON REDWOOD. Witnesses:

OLIVER IMRAY, Patent Agent, 28 Southampton Buildings,

London, W. C;

J NO. P. M. MILLARD, Clerk to Messrs. Abel &' Immy, Consulting Engineers(ml Patent Agents, 28 South:

(lmpfon Ell-tidings, London, W. C.

